Uraninite and chalcopyrite. Port Radium, Northwest Territories, Canada
Botryoidal, collomorphic uraninite (light grey, centre) encloses a rhombic carbonate (dark grey, centre). Fine-grained chalcopyrite (yellow, centre bottom) is abundant within uraninite. The carbonate gangue shows bireflectance (light and darker grey, top). Grey area (bottom) is resin.
Polished block, plane polarized light, x 40, air